1 #ifndef __LINUX_NETLINK_H
2 #define __LINUX_NETLINK_H
3
4 #include <linux/socket.h> /* for sa_family_t */
5 #include <linux/types.h>
6
7 #define NETLINK_ROUTE 0 /* Routing/device hook */
8 #define NETLINK_UNUSED 1 /* Unused number */
9 #define NETLINK_USERSOCK 2 /* Reserved for user mode socket protocols */
10 #define NETLINK_FIREWALL 3 /* Firewalling hook */
11 #define NETLINK_INET_DIAG 4 /* INET socket monitoring */
12 #define NETLINK_NFLOG 5 /* netfilter/iptables ULOG */
13 #define NETLINK_XFRM 6 /* ipsec */
14 #define NETLINK_SELINUX 7 /* SELinux event notifications */
15 #define NETLINK_ISCSI 8 /* Open-iSCSI */
16 #define NETLINK_AUDIT 9 /* auditing */
17 #define NETLINK_FIB_LOOKUP 10
18 #define NETLINK_CONNECTOR 11
19 #define NETLINK_NETFILTER 12 /* netfilter subsystem */
20 #define NETLINK_IP6_FW 13
21 #define NETLINK_DNRTMSG 14 /* DECnet routing messages */
22 #define NETLINK_KOBJECT_UEVENT 15 /* Kernel messages to userspace */
23 #define NETLINK_GENERIC 16
24 /* leave room for NETLINK_DM (DM Events) */
25 #define NETLINK_SCSITRANSPORT 18 /* SCSI Transports */
26 #define NETLINK_ECRYPTFS 19
27
28 #define MAX_LINKS 32
29
30 struct sockaddr_nl {
31 sa_family_t nl_family; /* AF_NETLINK */
32 unsigned short nl_pad; /* zero */
33 __u32 nl_pid; /* port ID */
34 __u32 nl_groups; /* multicast groups mask */
35 };
36
37 struct nlmsghdr {
38 __u32 nlmsg_len; /* Length of message including header */
39 __u16 nlmsg_type; /* Message content */
40 __u16 nlmsg_flags; /* Additional flags */
41 __u32 nlmsg_seq; /* Sequence number */
42 __u32 nlmsg_pid; /* Sending process port ID */
43 };
44
45 /* Flags values */
46
47 #define NLM_F_REQUEST 1 /* It is request message. */
48 #define NLM_F_MULTI 2 /* Multipart message, terminated by NLMSG_DONE */
49 #define NLM_F_ACK 4 /* Reply with ack, with zero or error code */
50 #define NLM_F_ECHO 8 /* Echo this request */
51
52 /* Modifiers to GET request */
53 #define NLM_F_ROOT 0x100 /* specify tree root */
54 #define NLM_F_MATCH 0x200 /* return all matching */
55 #define NLM_F_ATOMIC 0x400 /* atomic GET */
56 #define NLM_F_DUMP (NLM_F_ROOT|NLM_F_MATCH)
57
58 /* Modifiers to NEW request */
59 #define NLM_F_REPLACE 0x100 /* Override existing */
60 #define NLM_F_EXCL 0x200 /* Do not touch, if it exists */
61 #define NLM_F_CREATE 0x400 /* Create, if it does not exist */
62 #define NLM_F_APPEND 0x800 /* Add to end of list */
63
64 /*
65 4.4BSD ADD NLM_F_CREATE|NLM_F_EXCL
66 4.4BSD CHANGE NLM_F_REPLACE
67
68 True CHANGE NLM_F_CREATE|NLM_F_REPLACE
69 Append NLM_F_CREATE
70 Check NLM_F_EXCL
71 */
72
73 #define NLMSG_ALIGNTO 4U
74 #define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
75 #define NLMSG_HDRLEN ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
76 #define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(NLMSG_HDRLEN))
77 #define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
78 #define NLMSG_DATA(nlh) ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
79 #define NLMSG_NEXT(nlh,len) ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
80 (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
81 #define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
82 (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
83 (nlh)->nlmsg_len <= (len))
84 #define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
85
86 #define NLMSG_NOOP 0x1 /* Nothing. */
87 #define NLMSG_ERROR 0x2 /* Error */
88 #define NLMSG_DONE 0x3 /* End of a dump */
89 #define NLMSG_OVERRUN 0x4 /* Data lost */
90
91 #define NLMSG_MIN_TYPE 0x10 /* < 0x10: reserved control messages */
92
93 struct nlmsgerr {
94 int error;
95 struct nlmsghdr msg;
96 };
97
98 #define NETLINK_ADD_MEMBERSHIP 1
99 #define NETLINK_DROP_MEMBERSHIP 2
100 #define NETLINK_PKTINFO 3
101 #define NETLINK_BROADCAST_ERROR 4
102 #define NETLINK_NO_ENOBUFS 5
103
104 struct nl_pktinfo {
105 __u32 group;
106 };
107
108 #define NET_MAJOR 36 /* Major 36 is reserved for networking */
109
110 enum {
111 NETLINK_UNCONNECTED = 0,
112 NETLINK_CONNECTED,
113 };
114
115 /*
116 * <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
117 * +---------------------+- - -+- - - - - - - - - -+- - -+
118 * | Header | Pad | Payload | Pad |
119 * | (struct nlattr) | ing | | ing |
120 * +---------------------+- - -+- - - - - - - - - -+- - -+
121 * <-------------- nlattr->nla_len -------------->
122 */
123
124 struct nlattr {
125 __u16 nla_len;
126 __u16 nla_type;
127 };
128
129 /*
130 * nla_type (16 bits)
131 * +---+---+-------------------------------+
132 * | N | O | Attribute Type |
133 * +---+---+-------------------------------+
134 * N := Carries nested attributes
135 * O := Payload stored in network byte order
136 *
137 * Note: The N and O flag are mutually exclusive.
138 */
139 #define NLA_F_NESTED (1 << 15)
140 #define NLA_F_NET_BYTEORDER (1 << 14)
141 #define NLA_TYPE_MASK ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
142
143 #define NLA_ALIGNTO 4
144 #define NLA_ALIGN(len) (((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
145 #define NLA_HDRLEN ((int) NLA_ALIGN(sizeof(struct nlattr)))
146
147 #ifdef __KERNEL__
148
149 #include <linux/capability.h>
150 #include <linux/skbuff.h>
151
152 struct net;
153
nlmsg_hdr(const struct sk_buff * skb)154 static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
155 {
156 return (struct nlmsghdr *)skb->data;
157 }
158
159 struct netlink_skb_parms {
160 struct ucred creds; /* Skb credentials */
161 __u32 pid;
162 __u32 dst_group;
163 };
164
165 #define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb))
166 #define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds)
167
168
169 extern void netlink_table_grab(void);
170 extern void netlink_table_ungrab(void);
171
172 extern struct sock *netlink_kernel_create(struct net *net,
173 int unit,unsigned int groups,
174 void (*input)(struct sk_buff *skb),
175 struct mutex *cb_mutex,
176 struct module *module);
177 extern void netlink_kernel_release(struct sock *sk);
178 extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
179 extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
180 extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
181 extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
182 extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
183 extern int netlink_has_listeners(struct sock *sk, unsigned int group);
184 extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
185 extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
186 __u32 group, gfp_t allocation);
187 extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
188 __u32 pid, __u32 group, gfp_t allocation,
189 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
190 void *filter_data);
191 extern int netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
192 extern int netlink_register_notifier(struct notifier_block *nb);
193 extern int netlink_unregister_notifier(struct notifier_block *nb);
194
195 /* finegrained unicast helpers: */
196 struct sock *netlink_getsockbyfilp(struct file *filp);
197 int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
198 long *timeo, struct sock *ssk);
199 void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
200 int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
201
202 /*
203 * skb should fit one page. This choice is good for headerless malloc.
204 * But we should limit to 8K so that userspace does not have to
205 * use enormous buffer sizes on recvmsg() calls just to avoid
206 * MSG_TRUNC when PAGE_SIZE is very large.
207 */
208 #if PAGE_SIZE < 8192UL
209 #define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE)
210 #else
211 #define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL)
212 #endif
213
214 #define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
215
216
217 struct netlink_callback {
218 struct sk_buff *skb;
219 const struct nlmsghdr *nlh;
220 int (*dump)(struct sk_buff * skb,
221 struct netlink_callback *cb);
222 int (*done)(struct netlink_callback *cb);
223 int family;
224 long args[6];
225 };
226
227 struct netlink_notify {
228 struct net *net;
229 int pid;
230 int protocol;
231 };
232
233 static __inline__ struct nlmsghdr *
__nlmsg_put(struct sk_buff * skb,u32 pid,u32 seq,int type,int len,int flags)234 __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags)
235 {
236 struct nlmsghdr *nlh;
237 int size = NLMSG_LENGTH(len);
238
239 nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
240 nlh->nlmsg_type = type;
241 nlh->nlmsg_len = size;
242 nlh->nlmsg_flags = flags;
243 nlh->nlmsg_pid = pid;
244 nlh->nlmsg_seq = seq;
245 if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0)
246 memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
247 return nlh;
248 }
249
250 #define NLMSG_NEW(skb, pid, seq, type, len, flags) \
251 ({ if (unlikely(skb_tailroom(skb) < (int)NLMSG_SPACE(len))) \
252 goto nlmsg_failure; \
253 __nlmsg_put(skb, pid, seq, type, len, flags); })
254
255 #define NLMSG_PUT(skb, pid, seq, type, len) \
256 NLMSG_NEW(skb, pid, seq, type, len, 0)
257
258 extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
259 const struct nlmsghdr *nlh,
260 int (*dump)(struct sk_buff *skb, struct netlink_callback*),
261 int (*done)(struct netlink_callback*));
262
263
264 #define NL_NONROOT_RECV 0x1
265 #define NL_NONROOT_SEND 0x2
266 extern void netlink_set_nonroot(int protocol, unsigned flag);
267
268 #endif /* __KERNEL__ */
269
270 #endif /* __LINUX_NETLINK_H */
271